Container making apparatus and method



Aug. 29, 1961 w. B. ELAM 2,997,931

CONTAINER MAKING APPARATUS AND METHOD Filed April 11, 1960 2Sheets-Sheet 1 Z912 Q 329* )7 I? 2; 1 7 94 #12; W M

INVENTOR. W/ZZMM m/mw [MM BY Aug. 29, 1961 w. B. ELAM CONTAINER MAKINGAPPARATUS AND METHOD 2 Sheets-Sheet 2 Filed April 11, 1960 INVENTOR.W/ZZ/A'M AVA/F040 Fl/9M BY 2,997,931 CONTAINER MAIGN G APPARATUS ANDNETHOD William Binford Elam, Jersey City, N..I., assignor to AmericanCan Company, New York, N.Y., a corporation of New Jersey Filed Apr. 11,1960, Ser. No. 21,262 9 Claims. (Cl. 93-80) The present inventionrelates to the manufacture of spirally wound container bodies and hasparticular reference to a method and apparatus for maintaining controlover the free dangling ends of individual pull strings which aredisposed in a partially completed spirally wound tube in order toprevent the free pull string ends from becoming caught beneath andconcealed by an outer ply as the outer ply is added to the partlycompleted tube during the spiral winding operation.

In United States patent application Serial No. 729,366, filed in thename of Ralph K. Pottle and William B. Elam on April 18, 1958, andentitled Container, there is disclosed an improved easy openingcontainer wherein a pull string is incorporated in a spirally woundcontainer body. In this container body, the pull string comprises ahelically disposed portion which is positioned beneath one of the bodyplies and terminates in an end which passes through an opening the bodyply and then extends peripherally beneath a portion of a spirally woundlabel which covers the body ply. The string end passes between theoverlapped helical edges of the label to the outside of the container,where it can be readily seen and pulled to effect the opening of thecontainer.

A method and apparatus for securing these individual pull strings in abody ply web and then spirally winding such web and preprinted label plyinto a cylindrical tube from which individual container bodies aresubsequently cut is disclosed in United States application Serial No.19,872, filed on April 4, 1960, in the name of Ralph K. Pottle andentitled Machine and Method for Manufacturing Fibrous Container Bodies.

In the method disclosed in that application, the individual pull stringsare positioned, prior to the spiral winding operation, in longitudinalalignment in a body ply web with the major portion of each pull stringdisposed on one side of the web and the end of each pull string danglingfrom the opposite side of the web. This web is then spirally woundaround a mandrel in such a manner that these string ends are disposed onthe outside of the resulting partially completed tube, which almostimmediately thereafter is completely covered by a spirally wound labelwhich forms the external surface of the thus completed tube.

The present invention provides a means and method for insuring that thedangling ends of the individual pull strings are not completelyconcealed by the label web as it is wound onto: the tube, which, at suchtime is being rotated around the forming mandrel and advanced along itas an incident to the spiral winding operation so that the string endsare carried along a predetermined helical path of travel.

In order to accomplish this, these string ends, as the rotation andadvancement of the tube causes themto approach the line along which thelabel ply makes initial cont-act with the previously wound tube portion,are maintained in a rearwardly extending position to keep them clear ofthe rear marginal edge portion of the label web to prevent them frombeing caught beneath the rear portion of the label web. As the continuedrotation of the tube then causes these string ends to approach the areaat which the leading marginal edge portion of the label web makesinitial contact with the partially completed tube, the string ends areprojected forwardly in a direc- 2,997,931 Patented Aug. 29,1961

tion which is generally axially of the tube and are maintained in thisposition as the label web engages the tube. Because of the fact that thelength of these string ends exceeds the distance from the leading edgeof the label web to the points at which the string ends extend throughthe body ply, the outer portions of the string ends extend between thelabel seam and dangle freely from the finished tube. Thus, when the tubeis subsequently cut into in dividual container bodies, each body isprovided with an exposed string end which is easily grasped for thecontainer opening operation.

An object of the invention therefore, is the provision of a method ofpreventing the ends of individual pull strings which are secured in asubjacent body Web from being caught beneath and concealed by asubsequently applied label web during the container body windingoperation.

Another object is the provision of such a method wherein the pull stringends are first held in a rearwardly extended position to keep them clearof the rear edge of the label web and are then projected to a forwardlyextending position so that at least a portion of their length projectsforwardly beyond the leading edge of the label web as it is wound ontothe tube which carries the string ends.

Another object of the invention is the provision of means for carryingout the method steps of the invention.

Numerous other objects and advantages of the invention will be apparentas it is better understood from the following description, which, takenin connection with the accompanying drawings, discloses. a preferredembodiment thereof.

Referring now to the drawings:

FIGURE 1 is a perspective view of a finished container which embodies apull string having a free end which has been positioned in accordancewith the principles of the instant invention;

FIG. 2 illustrates a plan view of the preferred form of apparatussuitable for carrying out the method steps of the instant invention,parts being broken away;

FIG. 3 is a vertical section taken substantially along the line 3-3 inFIG. 1;

FIG. 4 is a fragmentary plan view of a portion of the apparatus of FIG.2, a portion of the label web being broken back to clearly illustratethe manner in which the string ends are projected forwardly in order toprevent them from being caught beneath the leading marginal edge portionof label Web;

FIG, 5 is a sectional view taken substantially along the line 55 in FIG.4;

FIG. 6 is an enlarged vertical section taken substantially along theline 6-6 in FIG. 5;

FIG. 7 is a plan of a modified form of apparatus wherein air blasts areused to perform the method steps or the instant invention;

FIG. 8 is an enlarged sectional view taken substantially along the line8-8 of FIG. 7;

FIG. 9 is a plan view showing a modified form of apparatus whereinvacuum alone is utilized to perform the method steps of the instantinvention; parts being shown in section and parts being broken away;

FIG. 10 is a sectional view on an enlarged scale taken substantiallyalong the line 1il10 of FIG. 9; and

FIG. 11 is a sectional View taken substantially along the line ll1l ofFIG. 9.

As a preferred and exemplary embodiment of the instant invention, FIGS.2 to 6 illustrate a machine for spirally winding a number of plies ofweb stock around a stationary winding mandrel 20 to combine them into aspirally wound tube generally designated by the numeral 22. In theinstant disclosure,'the tube 22 when completed is formed of four pliesof material, the first ply 3 comprising a liner ply 24 which is of awidth sufiicient to provide a lap joint on the inside of the tube 22.The undersurface of the liner ply 24 is coated with a suitable adhesive(not shown) as it approaches the mandrel 20.

Next comes a heavy body ply 26 which is wound onto the liner ply 24 withits edges in closely abutted relationship. The upper surface of this ply26 is coated with a suitable adhesive (not shown). A second heavy bodyply 28 is then wound onto the ply 26 with its edges abutted and disposedin offset relation to the butted edges of the ply 26. These three plies24, 26, 28 are passed through an endless winding belt 30 which isconventional in spiral winding machines of this type, and which impartsto the tube 22 the combination of a rotary motion around the mandrel anda forward motion along the mandrel 20 so that any given point on thetube 22 follows a helical path of travel.

The belt operates around a pair of spaced drums 32, 33 which arerespectively mounted on vertical shafts 34, 35 which are carried on apivoted frame 36 in the usual manner. The drums 3'2, 33 are rotated inopposite directions by a main drive belt 38 which operates around adrive pulley 40 which is keyed to a longitudinal drive shaft 42, thedrive shaft 42 being suitably connected to the shaft 34 of the drum 32by means of a pair of bevel gears (not shown). The rotation of the shaft42 1's also imparted to the drum 33 through a transverse connectingshaft 44.

As best seen in FIG. 2, the body ply 28 has positioned on it inlongitudinal alignment a plurality of individual pull strings P. Themajor portions M of these pull strings P are positioned on the uppersurface of this ply 28 and thus are disposed on the inside of the ply 28when it is wound around the mandrel 20. Each pull string P also includesat its trailing end an integral free end F which extends through anopening in the ply 28 and projects from the opposite surface of the ply28 so that they are disposed on the outside of the tube 22 as it passesthrough the winding belt 30.

After the tube 22 passes through the belt 3%, a label web 50 having itsundersurface coated with an adhesive (not shown) is guided ontothe topof the mandrel 20 by suitable guides 49 and is wound around the tube 22in such manner that it completely covers the outside of the tube 22 andprovides a decorative and protective label for it. For this purpose, theweb 50 may be composed of a suitable material such as a thin foillaminated to a thin paper backing sheet, and preferably has preprintedon it a suitable unitary label design (not shown) which occupies theareas generally indicated by the numerals 52. The label designs arepreferably printed on the diagonal, and are successively repeated alongthe ply 50, the individual label areas 52 {being separated from eachother along the diagonal lines 54 which may be real or imaginary andwhich become circumferential lines on the wound tube 22. It is alongthese circumferential lines that the cuts are subsequently made whichdivide the wound tube '22 into individual sections which compriseindividual container bodies such as the container body 55 seen in FIG.1'. The label web 50 is preferably of such width that its leading edgeportion overlaps its trailing edge portion in the finished tube 22 tothereby form a helically extending lap seam56. For this reason, thelapped portion 57 need not be printed with the label design. 7

As the partially finished tube 22 emerges from the winding belt 30 andapproaches the line, generally indicated by the broken line 58 in FIG.2, along which the label web 22 makes initial contact with it, it comesinto light frictional contact with a brush 59 which is mounted on ashaft 60 which is journalled in a suitable bearing 62. The bearing 62 ismountedron a vertically adjustable bracket 64 which in turn is supportedby a frame 66 which is mounted on a pivot pin67. The pivot pin 67 is in4 turn carried on a base 68 which is bolted to the main frame 69.

The brush 59 is preferably mounted so that its periphery is disposed inrearwardly spaced parallelism with the trailing edge 70 of the label Web50 as it approaches the mandrel 20, and is disposed in alignment withthe string ends F as they are carried along their helical path of travelalong the mandrel 20 by the tube 22. The brush 59 preferably is rotatedin a direction which is counter to the direction of the movement of thestring ends F by a spring belt 72 which operates around a pulley 74which is keyed to the shaft 60. At its other end, the belt 72 operatesaround a small pulley 76 which is keyed to a short shaft 78 mounted inthe frame 66. The shaft 78 also carries a large pulley 80 which isrotated by a belt 82 which, in turn, operates around and is rotated by apulley 34 mounted on a long longitudinal shaft 86 which extendsrearwardly of the machine and carries at its opposite end a secondpulley 88. The pulley 83 is rotated by a belt 90 which operates around apulley 92 which is keyed to the main drive shaft 42 and rotatestherewith.

The brush 59 is positioned so that it lightly engages the surface of thepartially formed tube and thus engages and exerts a dragging action oneach string end P as it passes beneath it. Prior to this engagement, thestring ends F dangle limply from the tube 22 in a generally verticaldirection. However, as a result of the dragging action exerted by thebrush 59, the string ends F are pulled into a position which issubstantially parallel to and rearwardly of the trailing edge 70 of thelabel web 50, and are maintained in this position during the time thelabel web 50 initially engages against the tube 22, adheres thereto andis carried forward by the rotation of the tube 22. Thus, the string endsF are maintained away from the label ply 50 and are not permitted to getinto a position where they would become caught beneath the rear marginalportions of the label Web 50 and be concealed from sight. It will beobvious that the brush 59 need not rotate to eifect a dragging action.However, rotation of the brush 59 is preferable to even the wear on itand to prevent the accumulation of paper fibres which it may pick upfrom the tube 22.

As the string ends F are rotated through approximately 270 after passingbeneath the brush 59, they pass from the control of the brush 59 andagain dangle limply from the outside surface of the tube 22. As

stated, the forward movement of the tube 22 causes these string ends Fto follow a helical path of travel. As a result, they again approach thelabel web 50 as it winds ontothe tube 22. Because of the fact that thediagonal dimension of the label web 50 is approximately equal to thepitch length of the helical path of travel of the string ends F, thestring ends F are now spaced behind the leading edge 96 of the label web50. In order to again prevent the string ends F from being caught beneath the label web 50, a second brush 100 is positioned adjacent themandrel 20 beneath the approaching label web 50.

The brush 100, as best seen in FIGS. 2 and 3, is disposed beneath thelabel web 50 and contacts the tube 22 at a point which intercepts thehelical path of travel of the string ends F. Consequently, the brushengages each of the string ends F as they are moved past it by therotation of the tube 22. The brush 100 is rotated in such direction thatat the area at which it contacts the tube 22, it is moving in the sameforward direction as is the tube, butpreferably at a peripheral speedwhich is about three times the forward speed of the tube. This rotationis transmitted from the shaft 78 through a pair of, bevel gears 102 tothe shaft 104 on which the brush 100 is mounted.

The brush 100 is forced against the tube 22 with a light pressure by aspring 105 which pulls the pivoted frame 66 inwardly toward the mandrel20. An adjustable stop 106 which engages against a stationary lug 107 isprovided to limit the pivotal movement of the carriage 66. A pivotedlatch 108 which is engageable against a pin 109 is provided to hold thecarriage in outward position when it is desired to hold the brushes 59,100 in non-operative position.

As a consequence of the forward rotation of the brush 100, the stringends F are thrown forwardly, as best seen in FIG. 4, so that they extendin a direction which is substantially longitudinal of the tube 22. ifthe brush 100 is spaced closely enough to the line of initial contact 58between the label web 50 and the tube 22, each string end F will remainsubstantially in this forwardly extending position until such time asthe rotation of the tube carries it past the line 58 with the resultthat a portion C of the string end F will be caught beneath the label,the remaining portion D of said string end P extending from between thelabel lap seam 56 and projecting therefrom to the outside of the tube22. In such case, the concealed portion C will extend substantiallyaxially of the tube 22. If the brush 100 is spaced farther from the line58, the string end F will have a tendency to sag downwardly by gravity,with the result that the portion C concealed beneath the label web 50will be inclined downwardly at an angle to the axis of the tube, but theouter end portion D of the string end F will still project from thelabel lap seam 56 and be exposed to view.

It is preferred, however, to provide means to positively hold the stringends F in their forwardly extended position as they pass the line ofcontact 58 between the label web 50 and the tube 22. For this purpose, avacuum head 108 is provided. The head 108 is connected to a suitablesource of vacuum such as a vacuum pump (not shown) by a vacuum pipe 109and is formed with an arcuate opening 110 which closely follows thecurvature of the tube 22 and extends from the brush 100 to the line ofcontact 58 (see FIG. 6) and is spaced just outwardly beyond the ends ofthe forwardly projecting string ends F. As a result, the string ends Fare pulled towards the arcuate opening 110 and maintained in the desiredposition as the label ply 50 wraps onto the tube 22.

The tube 22 is subsequently severed along the circumferential lines 54to divide it into individual can bodies 55, each of which contains aproperly located pull string having the portion D exposed to view. Asseen in FIG. 1, suitable end closures 111 are applied to the body endsto form a sealed package. When the consumer desires to open thecontainer to remove it contents (not shown), he need only pull outwardlyon the string portion D, thus tearing through the label ply 52 aloneuntil the tear reaches the point at which the string passes through thebody ply formed by the web 28. From thereon, the major string portion Mtears helically through both the label ply 50 and the body ply 28, thetear extending for the major length of the body 55. Since the stringportion M is positioned directly over the butt joint of the immediatelysubjacent body ply 26, thereafter only the comparatively thin liner ply24 holds the body 55 together and the thin ply 24 can be readily brokenby a twisting action exerted on the opposite ends of the body 55.

FIGS. 7 and 8 illustrate a modified form of the invention wherein blastsof air are utilized to effect the method steps of the invention. Thismodification comprises an air manifold 112 which receives a flow ofrapidly moving air through a supply pipe 113- from any suitable source,such as a blower (not shown). The air is divided in the manifold 112 bya pair of vertical bafiles 1 14, 116 and is diverted in oppositedirections forwardly and rearwardly of the mandrel 20. As seen in FIG.6, the baffle 114 is curved rearwardly so that it deflects a portion ofthe air backwardly along the mandrel 20 and blows the string ends Frearwardly to keep them from becoming caught beneath trailing edge 70 ofthe label web 50. In a similar manner, the baflie 116 is curvedforwardly and deflects a portion of the air forwardly along the mandrel20 so that the string ends F are projected in a forwardly extendingdirection as they approach the contact line 58 from beneath the labelweb 50. As seen in FIG. 7, the manifold front edges of the baffles 114,116 are curved around the mandrel 20 so that they are closely spacedtherefrom. Thus, the manifold is effective to direct the string ends Fright up to the line 58 at which the label web 50 comes into contactwith the tube 22.

FIGS. 9, 10 and 11 disclose another modified form of apparatus whereinthe method steps of the invention are effected solely by means ofvacuum. In this form, a vacuum nozzle 120 is positioned along thehelical path of travel of the string ends F with its opening slot 121 inclosely spaced relationship to the tube 22. A vacuum is constantlymaintained in the nozzle 12.0 by means of a suitable vacuum pump (notshown) which is connected to the nozzle 120 by a pipe 122. Thus, as therotation of the partially finished tube 22 causes the string ends F topass inwardly of the vacuum nozzle 120, a drag is exerted upon thestring ends F by the nozzle 120 and they are maintained rearwardly ofthe trailing edge 70 of the label web 50 as it winds onto the tube 22..Continued rotation of the 'tube 22 results in the helical movement ofthe string ends F which brings them into proximity to a second vacuumnozzle 124 which is mounted forwardly of the label web 50 and is formedwith a narrow opening 126 which extends arcuately around the tube from apoint just beneath the leading edge 96 of the label web 50 to a pointspaced forwardly of the initial line of contact 58 between the label web50 and the tube 22. Because of this shaping of the vacuum nozzle opening126, the string ends F are quickly pulled to and maintained in theposition shown in FIG. 9, wherein they extend forwardly of the leadingedge 06 of the label Web 50 as it winds onto the tube 22.

It will be understood that it is not necessary that the outer web 50 bea label web, nor that it be formed with a lap seam, since the methodsteps of the invention can be utilized to maintain the string ends Ffree of the superposed ply, regardless of whether such superposed ply bea heavy body ply or a thin label ply and regardless of whether thesuperposed ply be formed with a lap joint or a butt jointv It will alsobe obvious that the helical joint of the superposed ply need not beoffset from the helical path of travel of the string ends F, but may bepositioned in radial alignment with it; also that the method steps canbe effected by any suitable combination of brushes, vacuum and/or airblasts, and need not be limited to the specific combinations shown inthe drawings.

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and it will beapparent that various changes may be made in the form, construction, andarrangement of the parts of the apparatus mentioned herein and in thesteps and their order of accomplishment of the meth od described herein,without departing from the spirit and scope of the invention orsacrificing all of its material advantages, the apparatus and methodhereinbefore described being merely a preferred embodiment thereof.

I claim:

1. A method of forming spirally wound pull string container bodies,which comprises helically winding a web containing a plurality oflongitudinally disposed pull strings having free ends dangling therefromto form a tube With the ends of said pull strings dangling from theouter surface of the tube, rotating and advancing said tube along apredetermined path of travel, feeding a second web angularly to saidtube to bring it into contact with its outer surface and helicallywinding said second web onto said tube to cover it, maintaining saidstring ends rearwardly of the trailing edge of said second web as theadvancement androtation of said tube causes 2,997,9si A them to approachthe area at which said second web initially contacts said tube, andprojecting said string ends forwardly along said tube as thecontinuedadvancement and rotation of said tube causes them to approachthe leading edge of said second web at the area wherersaid secondwebinitially contacts said tube, whereby at least a portion of saidstring ends are kept from being caught beneathand covered by said secondweb.

2. A method of forming spirally wound pull string container bodies,which comprises helically wrapping around a horizontal mandrel an innerweb containing a plurality of longitudinally aligned pull strings havingfree ends dangling from said inner web to form said inner web into atube with the ends of said pull strings dangling from the outer surfaceof said tube, rotating and advancing said tube along said mandrel tomove said string ends along a helical path of travel, guiding an outerweb angularly of said tube into initial contact therewith at an areadisposed adjacent the top of said tube with the outer web so locatedthat its trailing edge is disposed in forwardly spaced relationship tothe adjacent portion of the helical path of travel" of the string ends,projecting said string ends rearwardly of said trailing edge of saidouter web as said outer web initially contacts said tube, and projectingsaid string ends forwardly along said mandrel as the continued rotationand advancement of said tube causes them to approach the leading edge ofsaid outer web at the area where said outer web initially contacts saidtube, whereby at least a portion of each tree string end is maintainedclear of said outer web.

3. A method of forming spirally wound pull string container bodies,which comprises spirally winding a body web containing a plurality oflongitudinally aligned pull strings having free ends dangling from saidweb to form said web into a tube with said string ends dangling from itsouter surface, rotating and advancing said tube to cause said stringends to follow a predetermined helical path of travel, guiding a labelweb angularly of said tube into contact with its outer surface, saidlabel web being so located as it initially contacts said tube that itstraddles one turn of the helical path of travel of said string ends,spirally winding said label web around said tube with its leading edgein overlapping engagement with its trailing edge portion to form a lapseam extending helically along said tube in offset relationship to thehelical path of travel of said string ends, maintaining said string endsrearwardly of said label Web as the advancement and rotation of saidtube causes them to approach the area at which said label web initiallycontacts said tube, and projecting said string ends forwardly along saidtube as the continued advancement and rotation of said tube causes themto approach the leading edge portion of said label web at the area wheresaid label web initially contacts said tube, whereby only the innerportions of said string ends are caught and concealed beneath said labelweb and the outer portions of said string ends extend through said labelweb lap seam and are exposed on the outside of said labelled tube.

8 a r a 4. A machine for forming spirally wound pull string containers,comprising a mandrel, means for'wrapping around said mandrel an innerweb which carries on it-a plurality of longitudinally disposed pullstrings having free ends dangling therefrom to form said inner web intoa tube wherein the string ends dangle from the outer surface of thetube, means to rotate said tube around and to advance said tube alongsaid mandrel to cause said string ends to follow a helical path oftravel, means for guiding an outer web into contact with said advancingtube with the trailing edge portion of said outer web disposed inparallelism with said helical path of travel of said string ends at thearea of initial contact between said outer Web and said tube, means formaintaining said string ends rearwardly of said trailing edge portion ofsaid outer web at said area of contact, and means for V projecting saidstring ends forwardly of the leading edge portion of said outer web tomaintain at least a portion of said string ends clear of said outer web.

5. The machine of claim 4, wherein the two last named means comprise apair of brushes engageable against said string ends, one of said brushesbeing effective in maintaining said string ends clear of said trailingedge and the other of said brushes being rotatable to project saidstring ends forwardly of the leading edge portion of said outer web.

6. The machine of claim 5 wherein vacuum means are provided to maintainsaid string ends in their forwardly projecting position after saidrotatable brush has projected them forwardly into such position.

7. A machine for forming spirally wound pull string containers,comprising a mandrel, means for wrapping around said mandrel an innerweb which carries on it a plurality of longitudinally aligned pullstrings having free ends which dangle from the web to form said web intoa tube with the string ends dangling from the outer surface thereof,means to rotate said tube around and to advance said tube along saidmandrel to cause said string ends to follow a helical path of traveltherealong, means for guiding an outer web angularly of said tube tobring it into contact therewith, means operable against said string endsas they approach the trailing edge of said outer Web for deflecting themrearwardly of said Web, and means operable against said string ends asthey approach the leading edge of said outerweb for projecting saidstring ends forwardly along said mandrel so that at least a portion ofeach of said string ends remain clear of said outer web and exposed onthe outer surface of said tube. j p

8. The machine of claim 7 wherein said two last named means projectblasts of air at said string ends.

9. The machine of claim 7 wherein said two last named means operate toattract said string ends by vacuum. e

No references cited.

